High-power oscillator tube



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Flled June 22, 1945 Nov. Z3, 1948.v J. E. GoRHAM A 2,454,279

HIGH POWER OSCILLATOR TUBE Filed June 22, 1945 zshets-sheet 2 INVENTOR.JOHN EfGORHAM `cumbersome and troublesome.

Patented Nov. 23, 1948 i UNITED STATES PATENT .OFFICE amended April 30,1928; 370 O. G. 757) The invention described herein may be manufacturedand used by or for the GovernmentI for governmental purposes, withoutthe payment to me of any royalty thereon, j

rlhis invention relates to oscillators, and more particularly toself-contained oscillator tubes.

Electron tubes have already been made which are nearly self-containedoscillators, particularly for the generation of ultrahigh frequencypower. Such tubes, however, have a number of disadvantages. The amountof power generated has been limited. Although tuned loops have beendisposed within the tube envelope for tuning the anode-to-anode andgrid-to-grid circuits, it has nevertheless been necessary totune thecathode-to-cathode circuit by means of an external circuit, which hassometimes proved In some tubes it has been necessary for a number ofstems and lead-ins to project in the same direction from the tubeenvelope at points relatively close to one another, thus making theconstruction o-f the tube a difficult glass-blowing job.

The primary .object of the present vinvention is to generally improveoscillator tubes, and more particularly ultra high frequency oscillatortubes having resonant loops Within the tube envelope. A more specificobject is to provide such a tube having greatly increased power output.Still another object is to facilitate tuning the cathode circuit byproviding capacitance loading between the cathodes, thereby reducing theinductance needed for resonance. In fact, in accordance with a furtherfeature and object of the invention, the necessary inductance may beprovided by a reduced length of cathode leadin housed within the tubeenvelope.

Still another object is to devise an oscillator tube in which nearly allof the lead-ins extend in different directions at widely spaced pointsvon the tube envelope, thus simplifying the` glassblowing job incidentto construction of the tube.

To accomplish the foregoing and Iother objects which will hereinafterappear, my invention resides in the oscillator tube elements, and theirrelation one to the other, as hereinafter are more particularlydescribed in the specification and sought to be defined in the claims.The specification is accompanied by a drawing in which Figure l is ahorizontal section through an oscillator tube embodying features 4of myinvention;

Figure 2 is a vertical section taken approximately in the plane of theline 2 2 of Figure l.;

faire i its @e end Vieweg@ kwieV Figure 4 is a detail showing thecathode;

Figure 5 is a detail showing the electrode assembly and cathode choke;

Figure 6 is a schematic diagram explanatory of the oscillator tube; andf Figure r7 is a detail similar to Figure 4, but showing a modification.

4Referring to the drawing, and more particularly to Figure 6, the tubecomprises a glass envelope I2 within which are disposed two electrodeassemblies, each comprising a cathode I4, a grid I6, andan anode I8. Aswill later appear when considering the structure of the tube, thecathodes are preferably disposed in end-to-end relation on a common axisWith the closed ends of the cathodes adjacent one another, therebyproviding a capacitance 20 which facilitates tuning of the cathodes byreducing the length of cathode lead-in needed for resonance. This lengthis symbolically defined or terminated by the chokes 22. These are shownoutside the tube envelope in Figure 6, and .may be located in thismanner, but as will later appear, they may also be housed within thetube envelope.

The anodes are connected to one another by a tuned loop 24, and thegrids are connected by a tuned loop 26, thus joining the two electrodeassemblies for push-pull operation. The loops 24 and 26 are locatedrelatively close together, thereby providing regenerative couplingtherebetween. `In the actual structure, it is convenient to `locate theloop 26 within the loop 24. While not essential, it is also convenientto make the structure symmetrical by the addition of equal,oppositely-extending loops 24 and 26'.

Referring now, to Figure 1 of the drawing, it will be seen that thecathodes I4 are hollow sheet metal cans, heated by means ofinternallycarried heater filaments 30. The cans are preferably coated onthe o-utside with a suitable electron emissive material, this being bestshown at 32 in Figure 4. The cathode can is vcarried by a lead-in 34which is preferably a hollow tubular ing a generally cylindrical cathodecan closed at its inner end, said end comprising a flat surfaceperpendicular to the longitudinal axis of said cathode, a cathodelead-in extending outwardly from said can,l a grid surrounding saidcathode, and an anode surrounding said grid, said electrode assembliesbeing disposed end-to-end ona common axis colinear with the axes of thecathodes, with the nat surfaces of the cathode assemblies adjacent oneanother whereby said surfaces form a radio-frequency condenser providingcapacitance loading for facilitating timing of the cathodes.

2. An ultrahigh frequency tube comprising a glass envelope carrying apair of electrode assemblies, each of said assemblies including acylindrical cathode can closed at its inner end, a cathode lead-inextending outwardly from said can, a grid surrounding said cathode, andan anode surrounding said grid, said electrodeassemblies being disposedend-to-end on a common axis with the closed ends of the cathodeassemblies adjacent one another providing cathode-tocathode capacitanceloading for facilitating tuning of the cathodes, the outwardlyoppositely projecting lead-ins of the cathodes having radio-frequencychokes within said envelope at -a point defining the inductance forproviding resonance with the aforesaid cathode-to-cathode capacitance.

3. An ultrahigh frequency tube comprising an evacuated glass envelopecarrying a pair of electrode assemblies, each of` said assembliesincluding a cylindrical cathode can closed at its inner end, said endcomprising a flat surface perpendicular to the longitudinal axis of'said cathode', a heater filament in said can, a cathode leadinextending outwardly from said can, a grid surrounding said cathode, andan anode surrounding said grid, said electrode assemblies being disposedend-to-end on a common axis colinear with` the axes of the cathodes withthe ilat surfaces of the cathode assemblies adjacent one another wherebysaid surfaces form a radio-frequency condenser, providingcathode-to-cathode capacitance loading for facilitating tuningof thecathodes, the outwardly oppositely projecting lead-ins of the cathodeshaving concentric chokes thereon within said envelope defining theinductance for providing resonance with the aforesaid cath-`ode-to-cathode capacitance.

4. An ultrahigh frequency oscillator tube comprising a glass envelopecarrying a pair of electrode assemblies and resonant loops, each of saidassemblies including a cylindrical cathodecan r closed at its inner end,said end comprising a flat surface perpendicular to the longitudinalaxis of said cathode, a heater lament in saidV can, a cathode lead-inextending outwardly from said can, a grid surrounding said cathode, andan anode surrounding said grid, said electrode assemblies being disposedend-to-end on a common axis colinear with the axes of the cathodes withthe flat surfaces of the cathode assemblies adjacent one another,whereby said surfaces form a radiofrequency condenser, one of theaforesaid loops being a grid-to-grid loop, and another loop being ananode-to-anode loop, said anode-to-anode loop enclosing the aforesaidgrid-to-grid loop.

5. An ultrahigh frequency oscillator tube comprising a glass envelopecarrying a pair of electrode assemblies and resonant loops, each of saidassemblies including a generally cylindrical cathode can closed at itsinner end, a heater filament in said can, a cathode lead-in extendingoutwardlyfrom said can, a grid surrounding said cathode, and an anodesurrounding said grid, said electrode assemblies being disposedend-to-end on a common axisv with the closed ends of the cathodeassemblies adjacent one another providing capacitance loading forfacilitating tuning of the cathodes, one of the aforesaid loops being agrid-to-grid loop, another loop being an anodeto-anode loop, theoutwardly oppositely projecting lead-ins of the cathode-s havingconcentric chokes thereon ata suitable point defining proper inductanceproviding resonance with the aforesaid cathode-to-cathode capacitance.

6. An ultrahigh frequency oscillator tube comprising an evacuated glassenvelope carrying a pair of electrode assemblies and resonant loops,each of said assemblies including a generally cylindrical cathode canclosed at its inner end, a heater filament in said can, a cathodelead-in exe tending outwardly from said can, a grid surrounding saidcathode, and an anode surrounding said grid, saidelectrode assembliesbeing disposed end-to-end on a common axis with the closed ends of thecathode assemblies adjacent one another providing capacitance loadingfor facilitating tuning of the cathodes, one of the aforesaid loopsbeing a grid-to-grid loop, another loop being an anode-to-anode loop,said anode-to-anode loop enclosing the aforesaid grid-to-grid` loop, theout- Wardly oppositely projecting lead-ins of the cathodes havingconcentric chokes thereon at a suitable point `defining properinductance providing resonance with the aforesaid cathode-to-cathodecapacitance, the aforesaid glass envelope enclosing the aforesaid loops,chokes and the electrode assemblies.

7. An ultrahigh frequency oscillator tube comprising a glass envelopecarrying a pair of ele-ctrode assemblies and four resonant loops, eachof said` assemblies including a generally cylindrical cathode can closedat its inner end, a heater filament in said can, a cathode lead-inextending loutwardly from said can, a grid surrounding said cathode, andan` anode surrounding said grid, said electrode assemblies beingdisposed end-toend on a common axis with the closed ends of the cathodeassemblies adjacent one another, two of the aforesaid loops beinggrid-to-grid loops extending in opposite direction, the other two loopsbeing anode-to-anode loops extending in opposite direction, saidanode-to-anode loops enclosing the aforesaid gr-id-to-grid loops.

8. An ultrahigh frequency oscillator tube comprising a glass envelopecarrying a pair of electrode assemblies and four resonant loops, each ofsaid assemblies including a generally cylindrical -cathode can closed atits inner end, a heater nlament in said can, a cathode lead-in extendingoutwardly from said can, a grid surrounding said cathode, and an anodesurrounding said grid, said electrode assemblies being disposedend-toend 'on a com-mon axis with the closed ends of the cathodeassemblies adjacentV one another, said ends providing a-cathode-to-cathode capac- -itan'ce loading for facilitating tuning ofthe cathodes, two of the aforesaid loops being grid-togrid loopsextending in opposite direction, the other two loops beinganode-to-anode loops extending in opposite direction, the outwardlyoppositely projecting lead-ins of the cathodes having concentric chokesthereon `ata suitable point defining proper inductance which forms aresonance circuit with the aforesaid Icathode-tocathode capacitance.

9. An ultrahigh frequency oscillator tube comprising an; evacuated glassenvelope .carrying a; pair of electrode assemblies and four resonant4loops, each of said-assemblies includingavgen-l erally cylindricalcathode can closed Iat its. inner end, a heater filament in said can,a-v cathode lead-inextending outwardlyrfrom said can, a grid surroundingsaid cathode, and an anode surrounding said grid, said electr-odeassemblies being disposed end-to-end on a common axis, with the closedends ofthe cathode. assemblies adjacent one another, said ends providinga cathodeto-cathode capacitance loading for facilitating.

cathode-to-cathode capacitance, theA aforesaid,

glass envelope enclosing the aforesaid loops, chokes and the electrodeassemblies.

10. An ultrahigh frequency oscillator tubecomprising a glass envelopecarrying a pair of electrode assembliesand resonant'loops, each'of saidassemblies including a cathode, a cathode lead-in extending horizontallyoutward from said cathode, a grid surrounding saidcathode,V

and an anode surrounding said grid, said electrode assemblies being.disposed end-,to-end ona common horizontalaxis, one of the aforesaidloops being a grid-to-grid loop, anotherloop be.

ing an ande-to-anode loop, said Vloops extending horizontally and saidanodetoanode loop enclosing saidy grid-to-grid loop, anode leadins`extending vertically upwardlyfrom the anodes,

and a grid loop support extending verticallyv downward from the nodalpoint of the grid loop, whereby nearly all of the lead-ins project indifferent directions at relatively widely spacedl p oints onthe glassenvelope of the tube.

11. An ultrahigh frequency oscillator tube comprising an evacuated glassenvelope carrying apair of electrode assemblies andresonant-loops,eachof said assemblies including a generally cylindrical cathode can, aheater filament in said can, a cathode lead-in extending horizontallyoutward from said can, a grid surrounding said cathode, and an anodesurrounding said grid, said electrode assemblies being disposedend-toend on a common horizontal axis, one of the aforesaid loops beinga grid-to-grid loop, another loop 4being an anode-to-anodeloop, saidloops extending horizontally and said anode-to-anode loop enclosing theaforesaid grid-to-grid loop, anode lead-ins extending verticallyupwardly from the anodes, and a grid loop support extending verticallydownward from the end of the grid loop, whereby nearly all of thelead-ins project in different directions at relatively widely spacedpoints on the glass envelope of the tube.

12. An ultrahigh frequency oscillator tube comprising aglass envelopecarrying a pair of electrode assemblies and four resonant loo-ps, eachof said assemblies including a cathode, a cathode lead-in extendinghorizontally outward from said cathode, a grid surrounding said cath'-ode, and an anode surrounding said grid, sa id electrode assembliesbeing disposed end-to-end' on a common horizontal axis, twoof theaforesaid loops being grid-to-gridl loops extending horizontally inoppositedirection, anode lead-ins projecting vertically upwardlyV lfromthe., anode-.- to-anode loops at the anodes, and grid loop lsup-i; ports`depending vertically downward'frorn the. nodal points of the gridl-oops, whereby nearly all,y of the lead-ins project in .differentdirectionsaatA relatively widely spaced pointson the glass envelope ofthe tube.

13. An ultrahigh frequency oscillator tubecom.

prising an evacuatedglass envelope carrying a pair of electrodeassemblies and four resonant loops, `each of said assemblies'including acylindrical cathode can, a heater filament in said can,

a cathode lead-in extending horizontally outward,

from said can, a grid surrounding said cathode, and an anode surroundingsaid grid, saidelectrode assemblies being disposed end-to-end on a'-common horizontal axis, two of the aforesaidloops being grid-to-gridloops extending in fop-4 posite direction, the other two loops beinganode-rl to-anode rloops extending in` opposite direction,

said loops extending horizontally and said anodef.

to-anode loops enclosing the aforesaid grid-togrid loops, anode lead-insprojecting vertically upwardly from the anode-toanode loops at theranodes, and grid loop supports depending ver.

tically downward from the nodal pointsv of the grid` loops, wherebynearly all ofA the lead-ins project in different directions atrelatively widely spaced points on the glass envelope of the tube.

14. An ultrahigh frequency oscillator tube com-v prising a-glassenvelope carrying a pair of electrode assemblies and four resonantloops, each of said assemblies includingfa cathode, a cathode lead-inextending horizontally outward lfrom said.Y

to-anode loop, the outwardly oppositely project, ing leads of thecathodes having concentricchokes thereon at a suitable point definingproper.

inductance forming a resonance circuit with theaforesaid'cathode-to-cathode capacitance, anode lead-ins projecting fromthe anodes in a direction normal to the plane of the loops andV cathodelead-ins, and a grid loop support connected to the nodal point of thegrid'loop.

15. An ultrahigh frequency oscillator tube comprising a glass envelopecarrying a pair of electrode assemblies and resonant loops, each of saidassemblies including a generally cylindrical cathode can closed at itsinner end, a tubular cathode lead-in extending horizontally outward fromsaid can, a grid surrounding said cathode, and an anode surrounding saidgrid, said electrode assemblies being disposed end-to-end on a commonaxis with the closed ends of thek cathode assemblies adjacent oneanother, said ends providing capacitance loading for facilitat-r ingtuning of the cathodes, one of the aforesaid loops being a grid-to-gridloop, another loop being an anode-to-anode loop, the outwardlyoppositely projecting leads of the cathodes having concentric chokesthereon at a suitable point defining proper inductance forming aresonance circuit with the aforesaid cathode-to-cathode capacitance,anode lead-ins projecting from the anodes in direction normal to theplane of the loops and cathode lead-ins, and a grid loop supportconnected to the nodal point of the grid loop.

16. An ultrahigh frequency oscillator tube com' prising a, glassenvelope carrying a pair of electrode assemblies and four resonantloops, each of said assemblies including a cylindrical cathode canclosed at its inner end, a heater filament in said can, a cathodelead-in extending horizontally outward from said can, a grid surroundingsaid cathode, and an anode surrounding said grid, said electrodeassemblies being disposed end-toend on a common axis with the closedends of the cathode assemblies adjacent one another, said ends providingcapacitance loading for facilitat ing tuning of the cathodes, one of theaforesaid loops being a grid-to-grid loop, another loop being ananode-to-anode loop, said anode-to-anode loop enclosing the aforesaidgrid-to-grid loop, the outwardly oppositely projecting leads of thecathodes having concentric chokes thereon at a suitable point definingproper inductance forming a resonance circuit with the aforesaidcathodeto-cathode capacitance, the aforesaid glass envelope enclosingthe aforesaid loops, chokes and the electrode assemblies, anode lead-insprojecting from the anodes in a direction normal to the plane of theloops and cathode lead-ins, and a grid loop support connected to thenodal point of the grid loop.

17. An ultrahigh frequency oscillator tube comprising a glass envelopecarrying a pair of electrode assemblies and four resonant loops, each ofsaid assemblies including a cylindrical cathode can closed at its innerend, a cathode lead-in extending horizontally outward from said can, agrid surrounding said cathode, and an anode surrounding said grid, saidelectrode assemblies being disposed end-to-end on a common axis with theclosed ends of the cathode assemblies adjacent one another, said endsproviding capacitance loading for facilitating tuning of the cathodes,two of the aforesaid loops being grid-to-grid loops extending inopposite directions, the other two loops being anode-to-anode loopsextending in opposite directions, the outwardly oppositely projectingleads of the cathodes having concentric chokes thereon at a suitablepoint defining proper inductance forming a resonance circuit with theaforesaid cathode-to-cathode capacitance, anode lead-ins projecting fromthe anodes in a direction normal to the plane of the loops and cathodeleadins, and grid loop supports projecting from the nodal points of thegrid loops in a direction opposite that of the anode lead-ins, wherebynearly all of the lead-ins project in different directions at relativelywidely spaced points on the glass envelope of the tube.

18. An ultrahigh frequency oscillator tube comprising a glass envelopecarrying a pair of electrode assemblies and four resonant loops, each ofsaid assemblies including a generally cylindrical cathode can closed atits inner end, a heater lament in said can, a tubular cathode lead-inextending horizontally outward from said can, a heater lead-in runningcoaxially through the tubular cathode lead-in, a grid surrounding saidcathode, and an anode surrounding said grid, said electrode assembliesbeing disposed end-to-end on a common axis with the closed ends of thecathode assemblies adjacent one another, said ends forming aradio-frequency condenser representing a capacitance loading forfacilitating tuning' of the cathodes, two of the aforesaid loops beinggrid-to-grid loops ex-tending in opposite directions, the other twoloops being anode-to-anode loops extending in opposite directions, saidanodeto-anode loops enclosing the aforesaid grid-togrid loops, theoutwardly oppositely projecting leads of the cathodes having concentricchokes thereon at a suitable point dening proper inductance forming aresonance circuit with the aforesaid cathode-to-cathode capacitance,anode lead-ins projecting from the anodes in direction normal to theplane of the loops and cathode lead-ins, and grid loops supportsprojecting from the nodal points of Ithe grid loops in a directionopposite that of the anode lead-ins, whereby nearly all of the lead-insproject in diierent directions at relatively widely spaced points on theglass envelope of the tube.

19. An ultrahigh frequency oscillator tube comprising an evacuated glassenvelope carrying a pair of electrode assemblies and four resonantloops, each of said assemblies including a generally cylindrical cathodecan closed at its inner end, a tubular cathode lead-in extendinghorizontally outward from said can, a grid surround ing said cathode,and an anode surrounding said grid, said electrode assemblies beingdisposed endto-end on a common axis with the closed ends of the cathodeassemblies adjacent one another, said ends providing capaci-tanceloading for facilitating the tuning of the cathodes, two of theaforesaid loops being grid-to-grid loops extending in oppositedirections, the other two loops being anode-to-anode loops extending inopposite directions, said anode-to-anode loops enclosing the aforesaidgrid-to-grid loops, the outwardly oppositely projecting leads of thecathodes having concentric chokes thereon at a suitable point definingproper inductance forming a resonance circuit with the aforesaidcathode-to-cathode capacitance, the aforesaid glass envelope enclosingthe aforesaid loops and chokes as well as the electrode assemblies,anode lead-ins projecting from the anodes in direction normal to theplane of the loops and cathode lead-ins, and grid loop supportsprojecting from the nodal points of the grid loops in a directionopposite that of the anode lead-ins, whereby nearly all of the lead-insproject in different directions at relatively widely spaced points onthe glass envelope of the tube.

JOHN E. GORI-IAM.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date Re. 20,602 Ruben Dec. 21, 19371,971,907 Found Aug. 28, 1934 1,979,668 Boddie Nov. 6, 1934 1,991,175Ruben i Feb. 12, 1935 2,042,345 Lindenblad May 26, 1936 2,119,675 GustinJune 7, 1938 2,170,657 Herzog Aug. 22, 1939 I 2,250,874 McCarthy July29, 1941

